Cotton variety st 4946glb2

ABSTRACT

The cotton variety ST 4946GLB2 is disclosed. The invention relates to seeds, plants, plant cells, plant tissue, harvested products and cotton lint as well as to hybrid cotton plants and seeds obtained by repeatedly crossing plants of variety ST 4946GLB2 with other plants. The invention also relates to plants and varieties produced by the method of essential derivation from plants of ST 4946GLB2 and to plants of ST 4946GLB2 reproduced by vegetative methods, including but not limited to tissue culture of regenerable cells or tissue from ST 4946GLB2.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser.No. 61/769,964, filed Feb. 27, 2013, the contents of which are hereinincorporated by reference in their entirety.

FIELD OF THE INVENTION

This invention relates to the field of plant breeding. Moreparticularly, the invention relates to a variety of cotton designated asST 4946GLB2, its essentially derived varieties and the hybrid varietiesobtained by crossing ST 4946GLB2 as a parent line with plants of othervarieties or parent lines.

BACKGROUND OF THE INVENTION

Cotton is an important, fiber producing crop. Due to the importance ofcotton to the textile industry, cotton breeders are increasingly seekingto obtain healthy, good yielding crops of excellent quality.

Cotton is commonly reproduced by self-pollination and fertilization.This type of sexual reproduction facilitates the preservation of plantand variety characteristics during breeding and seed production. Thepreservation of these characteristics is often important to plantbreeders for producing cotton plants having desired traits. Othermethods of producing cotton plants having desired traits are also usedand include methods such as genetic transformation via Agrobacteriuminfection or direct transfer by microparticle bombardment. Examples ofsuch methods are disclosed, for example, in U.S. Pub. No. 20090049564,incorporated by reference herein in its entirety.

Due to the environment, the complexity of the structure of genes andlocation of a gene in the genome, among other factors, it is difficultto predict the phenotypic expression of a particular genotype. Inaddition, a plant breeder may only apply his skills on the phenotype andnot, or in a very limited way, on the level of the genotype. As aresult, a particular plant breeder cannot breed the same variety twiceusing the same parents and the same methodology. Thus, a newly bredvariety is an unexpected result of the breeding process. Indeed, eachvariety contains a unique combination of characteristics.

By carefully choosing the breeding parents, the breeding and selectionmethods, the testing layout and testing locations, the breeder may breeda particular variety type. In addition, a new variety may be tested inspecial comparative trials with other existing varieties in order todetermine whether the new variety meets the required expectations.

SUMMARY OF THE INVENTION

The invention relates to seeds, plants, plant cells, parts of plants,cotton lint or fiber, and cotton textiles of cotton variety ST 4946GLB2as well as to hybrid cotton plants and seeds obtained by repeatedlycrossing plants of ST 4946GLB2 with other cotton plants. The inventionencompasses plants and plant varieties produced by the method ofderivation or essential derivation from plants of ST 4946GLB2 and toplants of ST 4946GLB2 reproduced by vegetative methods, including butnot limited to regeneration of embryogenic cells or tissue of ST4946GLB2. The invention also encompasses methods of producing cottonseeds that comprise crossing plants of cotton variety ST 4946GLB2 eitherwith itself or with a second, distinct cotton plant.

DETAILED DESCRIPTION OF THE INVENTION

The invention has been obtained by a general breeding process comprisingthe steps outlined below. For reference, see chapter 11, “BreedingSelf-Pollinated Crops by Hybridization and Pedigree Selection” in Briggsand Knowles (1967).

Parent plants, which have been selected for good agronomic and fiberquality traits are manually crossed in different combinations. Theresulting F1 (Filial generation 1) plants are self fertilized and theresulting F2 generation plants, which show a large variability onaccount of optimal gene segregation, are planted in a selection field.

These F2 plants are observed during the growing season for health,growth vigor, plant type, plant structure, leaf type, stand ability,flowering, maturity, seed yield, boll type, boll distribution, bollsize, fiber yield and fiber quality. Plants are then selected. Theselected plants are harvested and the bolls analyzed for fibercharacteristics and the seed cleaned and stored. This procedure isrepeated in the following growing seasons, whereby the selection andtesting units increase from individual plants in the F2, to multipleplant containing ‘lines’ (descending from one mother plant) in the F5and the number of units decrease from approximately 2500 plants in theF2 to 20 lines in the F5 by selecting about 10-20% of the units in eachselection cycle.

The increased size of the units, whereby more seed per unit isavailable, allows the selection and testing in replicated trials on morethan one location with a different environment and a more extensive andaccurate analysis of the fiber quality.

The lines or candidate varieties become genotypically more homozygousand phenotypically more homogeneous by selecting similar plant typeswithin a line and by discarding the so called off-types from the veryvariable F2 generation on to the final F7 or F8 generation.

Depending on the intermediate results the plant breeder may decide tovary the procedure described above, such as by accelerating the processby testing a particular line earlier or retesting a line another year.He may also select plants for further crossing with existing parentplants or with other plants resulting from the current selectionprocedure.

By the method of recurrent backcrossing, as described by Briggs andKnowles, supra, in chapter 13, “The Backcross Method of Breeding”, thebreeder may introduce a specific trait or traits into an existingvaluable line or variety, while otherwise preserving the uniquecombination of characteristics of this line or variety. In this crossingmethod, the valuable parent is recurrently used to cross it at least twoor three times with each resulting backcross F1, followed by selectionof the recurrent parent plant type, until the phenotype of the resultingF1 is similar or almost identical to the phenotype of the recurrentparent with the addition of the expression of the desired trait ortraits.

This method of recurrent backcrossing eventually results in anessentially derived variety, which is predominantly derived from therecurrent parent or initial variety. This method can therefore also beused to get as close as possible to the genetic composition of anexisting successful variety. Thus, compared to the recurrent parent theessentially derived variety retains a distinctive trait, which can beany phenotypic trait, with the intention to profit from the qualities ofthat successful initial variety.

Depending on the number of backcrosses and the efficacy of the selectionof the recurrent parent plant type and genotype, which can be supportedby the use of molecular markers as described by P. Stam (2003), thegenetic conformity with the initial variety of the resulting essentiallyderived variety may vary between 90% and 100%.

Other than recurrent backcrossing, as described herein, such essentiallyderived variety may also be obtained by the selection from an initialvariety of an induced or natural occurring mutant plant, or of anoccurring variant (off-type) plant, or of a somaclonal variant plant, orby genetic transformation of regenerable plant tissue or embryogeniccell cultures of the said initial variety by methods well known to thoseskilled in the art, such as Agrobacterium-mediated transformation asdescribed by Sakhanokho et al, (2004), Reynaerts et al. (2000), Umbecket al. (1988) and others. Examples of transgenic events transformed inthis way are “LLCotton25,” USDA-APHIS petition 02-042-01p, “Cot 102,”USDA-APHIS petition 03-155-01p, and “281-24-236,” USDA-APHIS petition03-036-01p combined with “3006-210-23,” USDA-APHIS petition 03-036-02p.Information regarding these and other transgenic events referred toherein may be found at the U.S. Department of Agriculture's (USDA)Animal and Plant Health Inspection Service (APHIS) website. An “Event”is defined as a (artificial) genetic locus that, as a result of geneticengineering, carries a foreign DNA comprising at least one copy of thegene(s) of interest. Other methods of genetic transformation are wellknown in the art such as microprojectile bombardment. See, e.g., U.S.Publication No. 20090049564, which is incorporated by reference hereinin its entirety.

The plants selected or transformed retain the unique combination of thecharacteristics of ST 4946GLB2, except for the characteristics (e.g.,one, two, three, four or five characteristics) changed by the selectionof the mutant or variant plant or by the addition of a desired trait viagenetic transformation. Therefore, the product of essential derivation(i.e., an essentially derived variety), has the phenotypiccharacteristics of the initial variety, except for the characteristicsthat change as a result of the act of derivation. Plants of theessentially derived variety can be used to repeat the process ofessential derivation. The result of this process is also a varietyessentially derived from said initial variety.

In one embodiment, ST 4946GLB2 progeny plants are produced by crossingplants of ST 4946GLB2 with other, different or distinct cotton plants,and further selfing or crossing these progeny plants with other,distinct plants and subsequent selection of derived progeny plants. Theprocess of crossing ST 4946GLB2 derived progeny plants with itself orother distinct cotton plants and the subsequent selection in theresulting progenies can be repeated up to 7 or 8 times in order toproduce ST 4946GLB2 derived cotton plants.

ST 4946GLB2 cotton contains four, simply-inherited events (GHB614,LLCOTTON25, MON531 and MON15985, respectively). The event GHB614 conferstolerance to glyphosate herbicides while the other event LLCOTTON25confers tolerance to glufosinate-ammonium herbicides. The events MON 531(Cry1Ac) and MON 15985 (Cry2Ab) provide lepidopteran control. These twoMON events were developed and licensed from Monsanto. A donor linecontaining the two MON events (MON531 and MON15985) and the LLCOTTON25event was crossed with another donor line containing the event GHB614.This F1 population donor parent was used to make the initial cross tothe recurrent parent of ST 4946GLB2. This cross was made inside aglasshouse located at the Bayer CropScience Research Station nearMemphis, Tenn. Three subsequent backcrosses were made. Following aselfing generation in the glasshouse, several plants were selected inthe field based on Cry 1Ac and Cry2Ab expression, tolerance toglyphosate herbicide, tolerance to glufosinate-ammonium herbicide, leafhair, disease resistance, lint % and fiber quality. Following progenyrow testing for yield, disease resistance and fiber quality, selectedlines proceeded to be tested in replicated trials, over multiple sites.At the same time small seed increases were initiated for all lines. ST4946GLB2 is a blend of selected lines. ST 4946GLB2 has been observed forseveral generations of reproduction. During this seed increase periodthe variety was stable and uniform. No variants were observed.

ST 4946GLB2 has an indeterminate plant growth habit and has a strong,erect central stem. ST 4946GLB2 is most similar to FM 1944GLB2; however,it has a significantly higher lint yield but shorter fiber.

Provided herein as embodiments of the invention are seeds, plants, plantcells and parts of plants of the cotton variety ST 4946GLB2.Representative seeds of this variety will be deposited under rule 37CFR1.809, prior to issuance of a patent. Applicant will make a deposit ofat least 2500 seeds of cotton variety ST 4946GLB2 disclosed herein withthe American Type Culture Collection (ATCC), 10801 University Boulevard,Manassas, Va. 20110-2209 USA. The accession number for the deposit isATCC Accession No. XXXXX. The seeds are deposited with the ATCC on dateYYYYY. Access to this deposit will be made available during the pendencyof the application to the Commissioner of Patents and Trademarks andpersons determined by the Commissioner to be entitled thereto uponrequest. The deposit will be maintained for a period of 30 years, or 5years after the most recent request, or for the enforceable life of thepatent, whichever is longer, and will be replaced if it becomesnonviable during that period. Applicant does not waive any rightsgranted under this patent or under the Plant Variety Protection Act (7U.S.C. 2321 et seq.).

Plants produced by growing such seeds are provided herein as embodimentsof the invention. Also provided herein are pollen or ovules of theseplants, as well as a cell or tissue culture of regenerable cells fromsuch plants. In another embodiment, the invention provides for a cottonplant regenerated from such cell or tissue culture, wherein theregenerated plant has the morphological and physiologicalcharacteristics of cotton cultivar ST 4946GLB2 when grown in the sameenvironmental conditions. In yet another embodiment, the inventionprovides methods of testing for a plant having the morphological andphysiological characteristics of cotton cultivar ST 4946GLB2. In oneembodiment, the testing for a plant having the morphological andphysiological characteristics of cotton cultivar ST 4946GLB2 isperformed in the same field, under the same conditions and in thepresence of plants of ST 4946GLB2, e.g., plants grown from the seeddeposited under Accession number XXXXX.

In another embodiment, the present invention provides regenerable cellsfor use in tissue culture of cotton cultivar ST 4946GLB2. The tissueculture will preferably be capable of regenerating plants having thephysiological and morphological characteristics of the cotton cultivarST 4946GLB2, and of regenerating plants having substantially the samegenotype as the cotton plant of the present invention. Preferably, theregenerable cells in such tissue cultures will be from embryos,protoplasts, meristematic cells, callus, pollen, leaves, anthers,pistils, roots, root tips, flowers, seeds, pods or stems. Still further,the present invention provides cotton plants regenerated from the tissuecultures of the invention.

Yet another aspect of the current invention is a cotton plant of thecotton variety ST 4946GLB2 comprising at least a first transgene,wherein the cotton plant is otherwise capable of expressing all thephysiological and morphological characteristics of the cotton variety ST4946GLB2. In particular embodiments of the invention, a plant isprovided that comprises a single locus conversion. A single locusconversion may comprise a transgenic gene which has been introduced bygenetic transformation into the cotton variety ST 4946GLB2 or aprogenitor thereof. A transgenic or non-transgenic single locusconversion can also be introduced by backcrossing, as is well known inthe art. In certain embodiments of the invention, the single locusconversion may comprise a dominant or recessive allele. The locusconversion may confer potentially any desired trait upon the plant asdescribed herein.

Single locus conversions may be implemented by a plant breedingtechnique called backcrossing wherein essentially all of the desiredmorphological and physiological characteristics of a variety arerecovered in addition to the characteristics conferred by the singlelocus transferred into the variety via the backcrossing technique. Asingle locus may comprise one gene, or in the case of transgenic plants,one or more transgenes integrated into the host genome at a single site(locus).

In a particular aspect, the invention provides for a method ofintroducing a single locus conversion into cotton cultivar ST 4946GLB2comprising: (a) crossing the ST 4946GLB2 plants, grown from seeddeposited under Accession No. XXXXX, with plants of another cotton linethat comprise a desired single locus to produce F1 progeny plants; (b)selecting F1 progeny plants that have the single locus to produceselected F1 progeny plants; (c) crossing the selected F1 progeny plantswith the ST 4946GLB2 plants to produce first backcross progeny plants;(d) selecting for first backcross progeny plants that have the desiredsingle locus and the physiological and morphological characteristics ofcotton cultivar ST 4946GLB2 when grown in the same environmentalconditions, to produce selected first backcross progeny plants; and (e)repeating steps (c) and (d) one or more times (e.g. one, two, three,four, etc. times) in succession to produce selected third or higherbackcross progeny plants that comprise the desired single locus and allof the physiological and morphological characteristics of cottoncultivar ST 4946GLB2 when grown in the same environmental conditions.Plants produced by this method have all of the physiological andmorphological characteristics of ST 4946GLB2, except for thecharacteristics derived from the desired trait.

Another embodiment of the invention provides for a method of producingan essentially derived plant of cotton variety ST 4946GLB2 comprisingintroducing a transgene conferring the desired trait into the plant,resulting in a plant with the desired trait and all of the physiologicaland morphological characteristics of cotton variety ST 4946GLB2 whengrown in the same environmental conditions. In another embodiment, theinvention provides for a method of producing an essentially derivedcotton plant from ST 4946GLB2 comprising genetically transforming adesired trait in regenerable cell or tissue culture from a plantproduced by the invention, resulting in an essentially derived cottonplant that retains the expression of the phenotypic characteristics ofcotton variety ST 4946GLB2, except for the characteristics changed bythe introduction of the desired trait.

Desired traits described herein include modified cotton fibercharacteristics, herbicide resistance, insect or pest resistance,disease resistance, including bacterial or fungal disease resistance,male sterility, modified carbohydrate metabolism and modified fatty acidmetabolism. Such traits and genes conferring such traits are known inthe art. See, e.g., US 20090049564, incorporated by reference herein inits entirety.

The invention also provides for methods wherein the desired trait isherbicide tolerance and the tolerance is linked to a herbicide such asglyphosate, glufosinate, sulfonylurea, dicamba, phenoxy proprionic acid,cyclohexanedione, triazine, benzonitrile, bromoxynil or imidazalinone.

In one embodiment, the desired trait is insect resistance conferred by atransgene encoding a Bacillus thuringiensis (Bt) endotoxin, a derivativethereof, or a synthetic polypeptide modeled thereon.

Also included herein is a method of producing cotton seed, comprisingthe steps of using the plant grown from seed of cotton variety ST4946GLB2, of which a representative seed sample will be deposited underAccession No. XXXXX, as a recurrent parent in crosses with other cottonplants different from ST 4946GLB2, and harvesting the resultant cottonseed.

Another embodiment of this invention relates to seeds, plants, plantcells and parts of plants of cotton varieties that are essentiallyderived from ST 4946GLB2, being essentially the same as this inventionby expressing the unique combination of characteristics of ST 4946GLB2,including the herbicide and insect resistance of ST 4946GLB2, except forthe characteristics (e.g., one, two, three, four, or five,characteristics) being different from the characteristics of ST 4946GLB2as a result of the act of derivation.

Another embodiment of this invention is the reproduction of plants of ST4946GLB2 by the method of tissue culture from any regenerable planttissue obtained from plants of this invention. Plants reproduced by thismethod express the specific combination of characteristics of thisinvention and fall within its scope. During one of the steps of thereproduction process via tissue culture, somaclonal variant plants mayoccur. These plants can be selected as being distinct from thisinvention, but still fall within the scope of this invention as beingessentially derived from this invention.

Another embodiment of the invention provides for a method of producingan inbred cotton plant derived from the cotton variety ST 4946GLB2comprising: (a) preparing a progeny plant derived from cotton variety ST4946GLB2, a representative sample of seed of said variety having beendeposited under ATCC Accession No. XXXXX, by crossing cotton variety ST4946GLB2 with a cotton plant of a second variety; (b) crossing theprogeny plant with itself or a second plant to produce a seed of aprogeny plant of a subsequent generation; (c) growing a progeny plant ofa subsequent generation from said seed and crossing the progeny plant ofa subsequent generation with itself or a second plant; and (d) repeatingsteps (b) and (c) for an additional 3-10 generations with sufficientinbreeding to produce an inbred cotton plant derived from the cottonvariety ST 4946GLB2.

Another embodiment of this invention is the production of a hybridvariety, comprising repeatedly crossing plants of ST 4946GLB2 withplants of a different variety or varieties or with plants of anon-released line or lines. In practice, three different types of hybridvarieties may be produced (see e.g., Chapter 18, “Hybrid Varieties” inBriggs and Knowles, supra):

The “single cross hybrid” produced by two different lines, the “threeway hybrid”, produced by three different lines such that first thesingle hybrid is produced by using two out of the three lines followedby crossing this single hybrid with the third line, and the “four wayhybrid” produced by four different lines such that first two singlehybrids are produced using the lines two by two, followed by crossingthe two single hybrids so produced.

Each single, three way or four way hybrid variety so produced and usingST 4946GLB2 as one of the parent lines contains an essentialcontribution of ST 4946GLB2 to the resulting hybrid variety and fallswithin the scope of this invention.

The invention also provides for cotton lint or fiber produced by theplants of the invention, plants reproduced from the invention, andplants essentially derived from the invention. The final textileproduced from the unique fiber of ST 4946GLB2 also falls within thescope of this invention. The invention also provides for a method ofproducing a commodity plant product (e.g., lint, cotton seed oil)comprising obtaining a plant of the invention or a part thereof, andproducing said commodity plant product therefrom.

The entire disclosure of each document cited herein (e.g., US patentpublications, non-patent literature, etc.) is hereby incorporated byreference.

DEPOSIT INFORMATION

Applicant will make a deposit of at least 2500 seeds of cotton varietyST 4946GLB2 disclosed herein with the American Type Culture Collection(ATCC), 10801 University Boulevard, Manassas, Va. 20110-2209 USA, onYYYYY under Accession No. XXXXX. Seed of cotton variety ST 4946GLB2 islocated at the Bayer CropScience Maricopa Cotton Breeding Station, 880 NPower Road, Bapschule, Ariz. 85121. The lot number for this seedmaterial is TQ2AR6176F. Access to this deposit will be available duringthe pendency of the application to the Commissioner of Patents andTrademarks and persons determined by the Commissioner to be entitledthereto upon request. The deposit will be maintained for a period of 30years, or 5 years after the most recent request, or for the enforceablelife of the patent, whichever is longer, and will be replaced if itbecomes nonviable during that period. Applicant does not waive anyrights granted under this patent or under the Plant Variety ProtectionAct (7 U.S.C. 2321 et seq.).

DEFINITIONS

In the description and tables which follow, a number of terms are used.In order to provide a clear and consistent understanding of thespecification and claims, the following definitions are provided:

A: When used in conjunction with the word “comprising” or other openlanguage in the claims, the words “a” and “an” denote “one or more.”

Allele: Any of one or more alternative forms of a gene locus, all ofwhich alleles relate to one trait or characteristic. In a diploid cellor organism, the two alleles of a given gene occupy corresponding locion a pair of homologous chromosomes.

Backcrossing: A process in which a breeder repeatedly crosses hybridprogeny, for example a first generation hybrid (F1), back to one of theparents of the hybrid progeny. Backcrossing can be used to introduce oneor more single locus conversions from one genetic background intoanother.

Cm to FFB: Measure of centimeters to first fruiting branch.

Crossing: The mating of two parent plants.

Cross-pollination: Fertilization by the union of two gametes fromdifferent plants.

Desired Agronomic Characteristics: Agronomic characteristics (which willvary from crop to crop and plant to plant) such as yield, maturity, pestresistance and lint percent which are desired in a commerciallyacceptable crop or plant. For example, improved agronomiccharacteristics for cotton include yield, maturity, fiber content andfiber qualities.

Diploid: A cell or organism having two sets of chromosomes.

Disease Resistance: The ability of plants to restrict the activities ofa specified pest, such as an insect, fungus, virus, or bacterial.

Disease Tolerance: The ability of plants to endure a specified pest(such as an insect, fungus, virus or bacteria) or an adverseenvironmental condition and still perform and produce in spite of thisdisorder.

Donor Parent: The parent of a variety which contains the gene or traitof interest which is desired to be introduced into a second variety.

E1: Refers to elongation, a measure of fiber elasticity (high=moreelastic).

Emasculate: The removal of plant male sex organs or the inactivation ofthe organs with a cytoplasmic or nuclear genetic factor conferring malesterility or a chemical agent.

Essentially all the physiological and morphological characteristics: Aplant having essentially all the physiological and morphologicalcharacteristics means a plant having the physiological and morphologicalcharacteristics, except for the characteristics derived from the desiredtrait.

F₁ Hybrid: The first generation progeny of the cross of two nonisogenicplants.

Fallout (Fo): As used herein, the term “fallout” refers to the rating ofhow much cotton has fallen on the ground at harvest.

FB5 cm to FFN: Measure of centimeters from main stem to first fruitingnode at fruiting branch 5.

2.5% Fiber Span Length: Refers to the longest 2.5% of a bundle of fibersexpressed in inches as measured by a digital fibergraph.

Fiber Characteristics: Refers to fiber qualities such as strength, fiberlength, micronaire, fiber elongation, uniformity of fiber and amount offiber.

Fiber Elongation: Sometimes referred to as E1, refers to the elongationof the fiber at the point of breakage in the strength determination asmeasured by High Volume Instrumentation (HVI).

Fiber Span Length: The distance spanned by a specific percentage offibers in a test specimen, where the initial starting point of thescanning in the test is considered 100 percent as measured by a digitalfibergraph.

Fiber Strength (Str): Denotes the force required to break a bundle offibers. Fiber strength is expressed in grams per tex on an HVI.

Fruiting Nodes: The number of nodes on the main stem from which arisebranches that bear fruit or boll in the first position.

Genotype: The genetic constitution of a cell or organism.

Gin Turnout: Refers to fraction of lint in a machine harvested sample ofseed cotton (lint, seed, and trash).

Haploid: A cell or organism having one set of the two sets ofchromosomes in a diploid.

Length (Len): The fiber length in inches using an HVI.

Linkage: A phenomenon wherein alleles on the same chromosome tend tosegregate together more often than expected by chance if theirtransmission was independent.

Lint Index: The weight of lint per seed in milligrams.

Lint Percent: The percentage of the seed cotton that is lint, handpickedsamples.

Lint Yield: Refers to the measure of the quantity of fiber produced on agiven unit of land. Presented below in pounds of lint per acre.

Lint/boll: As used herein, the term “lint/boll” is the weight of lintper boll.

Maturity Rating: A visual rating near harvest on the amount of openboils on the plant. The rating range is from 1 to 5, 1 being early and 5being late.

Micronaire (Mic): Refers to a measure of fiber fineness (high=coarsefiber) as measured with an HVI machine. Within a cotton cultivar,micronaire is also a measure of maturity. Micronaire differences aregoverned by changes in perimeter or in cell wall thickness, or bychanges in both. Within a variety, cotton perimeter is fairly consistentand maturity will cause a change in micronaire. Consequently, micronairehas a high correlation with maturity within a variety of cotton.Maturity is the degree of development of cell wall thickness.

Mr: Fiber maturity ratio.

Phenotype: The detectable characteristics of a cell or organism, whichcharacteristics are the manifestation of gene expression.

Plant Height: The average height in meters of a group of plants.

Quantitative Trait Loci (QTL): Quantitative trait loci (QTL) refer togenetic loci that control to some degree numerically representabletraits that are usually continuously distributed.

Recurrent Parent: The repeating parent (variety) in a backcross breedingprogram. The recurrent parent is the variety into which a gene or traitis desired to be introduced.

Regeneration: The development of a plant from tissue culture.

Seed/boll: Refers to the number of seeds per boll, handpicked samples.

Seedcotton/boll: Refers to the weight of seedcotton per boll, handpickedsamples.

Seedweight: Refers to the weight of 100 seeds in grams.

Self-pollination: The transfer of pollen from the anther to the stigmaof the same plant or a plant of the same genotype.

Single Locus Converted (Conversion) Plant: Plants which are developed bya plant breeding technique called backcrossing wherein essentially allof the desired morphological and physiological characteristics of avariety are recovered in addition to the characteristics conferred bythe single locus transferred into the variety via the backcrossingtechnique. A single locus may comprise one gene, or in the case oftransgenic plants, one or more transgenes integrated into the hostgenome at a single site (locus).

Stringout Rating: also sometimes referred to as “Storm Resistance”refers to a visual rating prior to harvest of the relative looseness ofthe seed cotton held in the boll structure on the plant. The ratingvalues are from 1 to 5 (tight to loose in the boll).

Substantially Equivalent: A characteristic that, when compared, does notshow a statistically significant difference (e.g., p=0.05) from themean.

T1: A measure of fiber strength, grams per tex (high=stronger fiber).

Tissue Culture: A composition comprising isolated cells of the same or adifferent type or a collection of such cells organized into parts of aplant.

Transgene: A genetic locus comprising a sequence which has beenintroduced into the genome of a cotton plant by transformation.

Uniformity Ratio (Ur): The proportion of uniform length fibers. Theuniformity ratio is determined by dividing the 50% fiber span length bythe 2.5% fiber span length.

Vegetative Nodes: The number of nodes from the cotyledonary node to thefirst fruiting branch on the main stem of the plant.

CITED REFERENCES

-   Lawrence P. Burdett, “Cotton Variety 02T15,” U.S. Pub. No.    20090049564.-   F. N. Briggs, and P. F Knowles, 1967:“Introduction to Plant    Breeding”, Rheinhold Publishing Corporation.-   H. F. Sakhanoko et al 2004:“Induction of Somatic embryogenesis and    Plant Regeneration in Select Georgia and Pee Dee Cotton Lines”, Crop    Science 44: 2199-2205.-   Umbeck et al 1988: “Genetic engineering of cotton plants and lines”,    Patent application number EP0290355.-   Reynaerts et al 2000: “Improved method for Agrobacterium mediated    transformation of cotton”, Patent application number WO 0071733.-   P. Stam, 2003: “Marker-assisted introgression: speed at any cost?”    Proceedings of the Eucarpia Meeting on Leafy Vegetable Genetics and    Breeding, Noordwijkerhout, The Netherlands, 19-21 Mar. 2003. Eds.    Th. J. L. van Hintum, A. Lebeda, D. Pink, J. W. Schut. P 117-124.-   Trolinder et al. “Herbicide tolerant cotton plants having event    EE-GH1.” U.S. Pat. No. 6,818,807 (2004).

EXPERIMENTAL EXAMPLE Characterization of Cotton Variety ST 4946GLB2

ST 4946GLB2 has an indeterminate plant growth habit and has a strong,erect central stem. ST 4946GLB2 is most similar to FM 1944GLB2; however,it has a significantly higher lint yield but shorter fiber. Data trialsconsisted of three replications of two-row plots in a RandomizedComplete Block Design. Plots were 13 m long with approximately 210plants per plot (stand counts were not recorded). Individual plots weremechanically harvested and weighed. A sample of seedcotton from each oftwo replications was ginned on Continental 10-saw gins and fiber sampleswere analyzed on an Uster 1000 HVI machine.

TABLE 1 Data from 2012 replicated testing in 2012 in Dawson County, TX.Entry Name N Yield Len ST4946GLB2 3 1249 1.12 FM1944GLB2 3 864 1.15LSD(.05) 243 0.02 CVErr 10.147 0.947

TABLE 2 Data from 2012 replicated testing in 2012 in Newellton, LA.Entry Name N Yield Len ST4946GLB2 3 1863 1.15 FM1944GLB2 3 1543 1.19LSD(.05) 60 0.02 CVErr 1.543 0.427

TABLE 3 Data from 2012 replicated testing in 2012 in Garza, TX EntryName N Yield Len ST4946GLB2 3 1441 1.10 FM1944GLB2 3 1289 1.17 LSD(.05)109 0.02 CVErr 3.523 0.442

TABLE 1 Characteristics of ST 4946GLB2 Variety Description ofcharacteristic Possible expression/note ST 4946GLB2 FM 944GLB2 GeneralPlant Type Plant Habit spreading, intermediate, compact CompactIntermediate Foliage sparse, intermediate, dense IntermediateIntermediate Stem Lodging lodging, intermediate, erect Erect ErectFruiting Branch clustered, short, normal Normal Short Growthdeterminate, intermediate, Intermediate Intermediate indeterminate Leafcolor greenish yellow, light green, medium Medium Green Medium Greengreen, dark green Boll Shape Length < Width, L = W, L > W Length > WidthLength > Width Boll Breadth broadest at base, broadest at middle MiddleMiddle Maturity Days till maturity August 24 August 28 Plant cm. tofirst Fruiting Branch from cotyledonary node 15.5 17.3 No. of nodes to1st Fruiting excluding cotyledonary node 5.0 6.2 Branch Mature PlantHeight in cm. cotyledonary node to terminal 96.1 100.4 Leaf: upper most,fully expanded leaf Type normal, sub-okra, okra, super-okra NormalNormal Pubescense absent, sparse, medium, dense Medium Sparse Nectariespresent, absent Present Present Stem Pubescense glabrous, intermediate,hairy Intermediate Intermediate Glands (Gossypol) absent, sparse,normal, more than normal Leaf Normal Normal Stem Normal Normal Calyxlobe (normal is absent) Normal Normal Flower Petals cream, yellow CreamCream Pollen cream, yellow Cream Cream Petal Spot present, absent AbsentAbsent Seed Seed Index g/100 seed fuzzy basis 11.45 10.85 Lint Index glint/100 seeds 8.00 7.11 Boll Lint percent Gin Turnout, picked 0.3980.404 Number of Seeds per Boll 29.44 38.38 Grams Seed Cotton per Boll3.37 3.08 Number of Locules per Boll 4.3 4.4 Boll Type storm proof,storm resistant, open Open Open Fiber Properties HVI method Length,inches, 2.5% SL 1.17 1.22 Uniformity (%) 83.9 83.7 Strength, T1 (g/tex)31.0 31.4 Elongation, E1 (%) 6.8 5.2 Micronaire 4.49 4.43

1. A seed of cotton variety ST 4946GLB2, wherein a representative seed of said variety was deposited under ATCC Accession No. XXXXX.
 2. A plant, or a part thereof, produced by growing the seed of claim
 1. 3. A plant, or a part thereof, obtained by vegetative reproduction from the plant, or a part thereof, of claim 2, said plant, or a part thereof, expressing all the phenotypic characteristics of cotton variety ST 4946GLB2, a sample of seed having been deposited under ATCC Accession No. XXXXX.
 4. A process of vegetative reproduction of cotton variety ST 4946GLB2 comprising, culturing regenerable cells or tissue from ST 4946GLB2, a sample of seed having been deposited under ATCC Accession No. XXXXX.
 5. A cell or tissue culture produced from the plant, or a part thereof, of claim
 2. 6. A cotton plant regenerated from the cell or tissue culture of claim 5, said plant expressing all the phenotypic characteristics of ST 4946GLB2, a sample of seed having been deposited under ATCC Accession No. XXXXX.
 7. A method of producing a Fl hybrid cotton seed, comprising the steps of crossing the plant of claim 2 with a different cotton plant and harvesting the resultant F1 hybrid cotton seed.
 8. A F1 hybrid cotton seed produced by the method of claim
 7. 9. A F1 hybrid cotton plant, or part thereof, produced by growing the hybrid seed of claim
 8. 10. A plant obtained by the vegetative reproduction of the cotton plant of claim
 9. 11. A method of producing a cotton seed comprising the steps of crossing the plant of claim 10 with a different cotton plant and harvesting the resultant cotton seed.
 12. A method of introducing a desired trait into a cotton plant, the method comprising, transforming the plant of claim 2 with a transgene that confers the desired trait, wherein the transformed plant retains all the phenotypic characteristics of cotton variety ST 4946GLB2 and contains the desired trait.
 13. The method of claim 12, wherein said desired trait is fiber quality, herbicide resistance, insect resistance, bacterial disease resistance or fungal disease resistance.
 14. A method of introducing a desired trait into a cotton plant, the method comprising transforming the plant of claim 9 with a transgene that confers the desired trait, wherein the transformed plant retains all the phenotypic characteristics of cotton variety ST 4946GLB2 and contains the desired trait, seed of said variety having been deposited as ATCC Accession No. XXXXX.
 15. A cotton plant produced by the method of claim
 12. 16. A method of introducing a single locus conversion into cotton variety ST 4946GLB2 comprising: (a) crossing a plant of variety ST 4946GLB2 with a second plant comprising a desired single locus to produce F1 progeny plants; (b) selecting F1 progeny plants that have the single locus to produce selected F1 progeny plants; (c) crossing the selected progeny plants with at least a first plant of variety ST 4946GLB2 to produce backcross progeny plants; (d) selecting backcross progeny plants that have the single locus and all physiological and morphological characteristics of cotton variety ST 4946GLB2 to produce selected backcross progeny plants; and (e) repeating steps (c) and (d) one or more times in succession to produce selected second or higher backcross progeny plants that comprise the single locus and otherwise comprise all of the physiological and morphological characteristics of cotton variety ST 4946GLB2 when grown in the same environmental conditions.
 17. The method of claim 16, wherein the single locus confers a trait selected from the group consisting of male sterility; herbicide tolerance; insect or pest resistance; disease resistance; modified fatty acid metabolism; modified carbohydrate metabolism; and modified cotton fiber characteristics. 